A Soft Landings Planting Beneath a Keystone Tree

Connecting Habitat Neighbor-to-Neighbor

by Vicki Bonk

Part 1- February 2023   Part 2- March 2023

Part 1- February 2023

Now, is a very good time to consider spring planting plans. First, you can momentarily transport yourself to the spring greening and warming of the landscape. Secondly, you can get ready to make the most of the growing season soon to arrive.

We all begin our gardening plans at different places. I’ll relay our small, urban home plans to enhance our native plantings. We began growing native habitat in the late 90s. This year we’ve decided to do another Soft Landings Project, like the one pictured. For a wealth of valuable information about this inspirational vision of two Minnesota locals, working alongside Douglas Tallamy*, please visit https://www.pollinatorsnativeplants.com/softlandings.html. Succinctly, the idea is to plant native species beneath keystone trees (those that support a significant number of butterfly and moth larvae), in order to allow these insects the opportunity to complete their life cycle. This shady planting also attracts and helps sustain a diversity of native pollinators, beneficial insects, and birds, throughout the year.

Here is our Northside Soft Landings Project site in May and September. The plantings are under a Pin Oak and an Autumn Blaze Serviceberry (cultivar). Plants were chosen to offer blooms throughout the season.

The spring bloomer list includes: Solomon’s Seal, Wild Columbine, Wild Geranium, Jacob’s Ladder, Meadow Rue, Jack-in-the Pulpit, Violets, Woodland Strawberry, Pennsylvania Sedge, Blood Root, Wild Ramps, Bellwort, Wild Ginger and Wild Blue Phlox.

Later in the year, Heart-leaved Aster, Big-leaved Aster and Zig-zag Goldenrod show up among the present Lady Ferns, Maiden Hair Ferns and sedge varieties.

These plants thrive in our increasingly shady yard. The same plant species are prevalent in nearby wild areas along the Mississippi River. I have found this selection works quite well so the plan is to extend more on the increasingly shady southside that lies heavily shaded under our neighbor’s Sugar Maple. Since the neighbor is on board, we’ll plant in her yard too! This location of our next Soft Landings project is indeed, connecting and growing habitat!

Watch a Douglas Tallamy video about native keystone plants.

https://www.nwf.org/Garden-for-Wildlife/About/Resources/native-keystone-plants

A photo shows the Soft Landings pictured previously. In front, is a sloped rock retaining wall, constructed with local limestone. Importantly, there is signage that tell passersby what this landscape is about - HABITAT! We maintain clean but natural edges.

We also have a GROW HABITAT Free Info Box, conveniently located next to the sidewalk.

Here’s the lay of the land:

• We have no lawn, basically “green mulch” is provided by low groundcovers including Blue and Canada Violets, Woodland Strawberries and Wild Ginger.
• Fallen leaves are left as mulch to rebuild the soil, help retain moisture and provide insect habitat.
• Future plantings will be additionally mulched by oak leaves from nearby, as well as the maple.
• Log habitat features are in this area, now hidden under the snow.
• Native plants, preferring part-shade to shade growing conditions, here now include: Heart-leaved Aster, Zig-Zag Goldenrod, Elm-leaved Goldenrod, American Bellflower, Thimbleweed, Oval Sedge, Alumroot, Poke Milkweed, Lady’s Fern, Jack-in-the Pulpit, Wild Ramps. Dwarf Bush Honeysuckle is on a sunnier edge.
• A number of plants requiring more sun are here but not thriving. This area received more sun in earlier days before the maple shade grew. The species include Wild Bergamot, Culver’s Root, Brown-eyed Susan, New England Aster, and Common Milkweed. There was a Red-twigged Dogwood with changing conditions so we reluctantly removed last fall. We will eventually relocate plants not doing well.
• We are seeking native species to plant here that can tolerate drier soil conditions. Our soil is a little sandy and droughtier conditions have prevailed the last few years. Climate change is happening and we’re going to plant accordingly.
• We are looking for an understory tree or shrub to plant. Being considered at the moment, is the native Witch Hazel that is tolerant to a range of sun and soil conditions. It has ornamental value and the yellow flowers bloom in late fall, attracting the few remaining pollinators. Nice to end the season on a colorful bloom note!
• We did some Winter Sowing in containers this year that included Short’s Aster, a shady aster new to our yard and to be planted here.
• Next step is looking for plants to add diversity. A go-to resource is Prairie Moon Nursery catalog and is also online. https://www.prairiemoon.com We’ll be ordering their Bellwort for a dormant bare roots delivery. Their catalog helps me document and select our list of yard plants. We are fortunate to have many native plant nurseries in the area and we seek their offerings often. Wild Ones Twin Cities has many resources including a nursery guide and design templates. http://www.wildonestwincities.org
• Additional resources, including planting templates and plant lists, can be found on BWSR's Lawns to Legumes website
• During the next month, will be making further plans and selections!

Workshop?

If there is interest, we could do an in-person workshop on design and plant selection. Please email Sue if you are interested in attending a workshop at our chapter.

Part 2- March 2023

Recap: This is the second article on the habitat gardening plans to augment a shady understory area beneath our neighbor’s Sugar Maple that extends into our bit of Minneapolis urban land. It’s a process! To learn more about Soft Landings and the project refer to the March blog.

A 2023 native plant catalog arrived in the mailbox today, and brought with it, a refreshed outlook. The cover photo featured American Bellflower (Campanula americana), whose deep blue blooms were being visited by the federally endangered Rusty Patched Bumble Bee (Bombus affinis). Double wow! This bellflower is not to be confused with the highly invasive Creeping Bellflower, (Campanula rapunculoides), seen throughout our area and zeroing in right next door. The captivating cover resonated on two opposing fronts. First, the American Bellflower does well in shade and is a welcome addition to a Soft Landings planting. Secondly, the Creeping Bellflower persists in my neighbor’s yard and managing this ecologically troublesome plant, is difficult and time consuming. * A job for the pitchfork, then down on your hands and knees, to dig through soil searching for every last remnant of the plant. (Our Chapter Caretaker, Paul Erdmann has renamed Creeping Bellflower- Creeping “Hellflower” and notes that it is one of the worst weeds at the Chapter, and it was likely planted by some good intentioned, but clueless, person). In that one glance at the catalog cover, I went through the glory and the pain of stewarding land. Yet not to be discouraged by creeping bellflower but encouraged by the potential our bit of land connecting with neighbor’s has now and can hold in the future.

Plant Considerations

With plant selection, I look into four main areas: what to keep, what to add, what to manage (reduce or remove) and what do we especially wish to see take place at our place. What plants to keep are often those that are thriving. Why are they doing so well? What are the plant requirements in terms of light and soil conditions? How are they part of a developing plant community and what wildlife are they inviting? What plants to add, looks at the present plant community with an eye to what is realistically possible and then asks what is missing in seasonal blooms, in wildlife benefit, in canopy level (groundcover, plant heights, shrubs, tree) and design interest. What plants to reduce or remove, considers what over-zealous plants might be hindering a more biodiverse plant community and whether invasive plants are present that require management. Finally, a heartfelt look at what you enjoy having around your homeland, serves to inspire the planning process and encourage your curiosity to learn more. Ask yourself, “what do I love and want to see unfold on my bit of land”?

The Central Keystone Tree

This project centers on a Soft Landings planting beneath an existing mature Sugar Maple (Acer saccharum), a keystone species, a native plant all-star, as in highly significant (and often critical) to their food web. How is the sugar maple ecologically valuable? Beginning with the indigenous people, many North Americans, have a long history of harvesting and enjoying maple syrup. We easily recognize the awesome value of the Sugar Maple’s spectacular fall color. Yet, many of the ecological services aren’t so obvious. Bees, butterflies, and birds also drink in the energy-giving sap. Maples flower in early spring, attracting a variety of bee species including mining, sweat, cellophane and mason. The leafy foliage serves as the host plant food for over 220 moth and butterfly species in our area alone. This is vital to these lepidoptera insects AND to the food web. The National Wildlife Fund states that 96% of U.S. terrestrial birds rely on insects supported by keystone plants. These birds require a fatty, protein-rich food source to feed their young and nothing tops juicy caterpillars. The maple fruit is eaten by adult songbirds. Many birds like to nest in the trees, right alongside their food sources. The fruit, buds and twigs are eaten by several mammals including deer, chipmunks, and squirrels. Decomposing maple leaves enrich the surrounding soil by raising the soil’s mineral content and making it less acidic. This gives plant roots increased access to nutrients and water. Maples help prevent erosion sequester carbon and help manage storm water runoff - all with their expansive root system. Much of this done, all in a day, quite quietly.

The Soft Landings project aims to plant specific natives, surrounding this tree, so that beneficial insects that begin their life cycle in the upper tree canopy, can complete their life cycle below. This planting will also build a healthier soil, provide moisture-retaining green mulch, give food and shelter for a variety of pollinators, beneficial insects and birds, and further carbon sequestration.

Plant Stories

More diverse and effective habitats have varying height levels where wildlife can interact to find food and shelter. The Sugar Maple is providing the tallest level. In our spatially limited setting, there is room for one understory tree or a tall shrub, a bit past the Maple canopy dripline and also for several short shrubs nearby. Within the dripline area, plants of various heights and shorter ground covers will complete the layered stories. Small seedlings only will be planted within the dripline, to avoid digging into the ground too deeply and disturbing the maple roots.

Understory Trees and Shrubs

Our site specifics of partial shade to full shade and medium to medium/dry soil, plus wildlife value, narrow plant selection choices. At this time, a strong contender for a larger attractive shrub is Round-leaved Dogwood (Cornus rugosa), which does well in drier soil and less sun while offering strong wildlife and ecological value. Here is Prairie Moon’s write-up “This woodland understory tree-like-shrub has full-season interest: lovely white clusters of flowers in spring, bushy green foliage in summer, attractive berry-like drupe clusters in fall, and yellow-green branches with reddish-purple markings that are striking against the white winter snow. Round-leaved Dogwood prefers thin canopies with dappled sunlight and woodland edges. Sometimes this Dogwood will grow from one branch, appearing more like a tree. Other times it will grow from multiple stems, appearing more like a shrub. Pruning will encourage a more dense, shrubby appearance.

The Round-leaved Dogwood is a great plant for insects and wildlife. It is one of the host species for the Spring Azure butterfly and Gossamer Wing butterfly. The fruits are eaten by multiple species of grouse, and the twigs are eaten by mammals like deer and rabbit. In some Eastern states, Round-leaved Dogwood is rare or endangered.”

We currently have one shorter shrub variety in this area, Dwarf Bush Honeysuckle (Diervilla lonicera), an easy-to-grow shrub adaptable to many soil types and all light levels plus is drought tolerant. The flowers attract bumble bees, butterflies, moths and butterflies. Considering adding two more but need to factor growing spatial width since they are suckering plants. That could be an advantage on the sloped area. I bought this shrub at a new nursery in our Minneapolis neighborhood, The Agrarian, who have a good selection of natives.

Understory Forbs, Ferns, Sedges and Groundcovers

Awaiting the highly anticipated arrival of spring in our yard, means looking for the emergence of Bloodroot (Sanguinaria candensis), one of the first Minnesota native plants to bloom. The love of this plant influences some further understory planting deliberations. As the weather warms, we faithfully check the bloodroot progress from their leafy bed, happening anytime from late March to late April, depending on that year’s weather. Bloodroot has a sweet spot in our front rock garden’s north corner, nestled between Wild Ginger (Asarum canadense) and Maidenhair Fern (Adiatum pedatum). The newly inspired gardening plan is for the trio to have a spot on the south corner of the rock garden, which extends into the Maple Soft Landing’s location. These plants could attractively bookend our urban lot. No rigidity but a continuity that could help organize the small space. The plan is to gently dig-up, then divide some of the wild ginger and maidenhair fern, just as they break soil in the spring, their best time to transplant. We’ll wait to transplant Bloodroot, their best transplant time is early summer, when the plant is starting to go dormant.

By propagating and transplanting natives that are growing well here, we are planting species that are suited to the site while saving money and avoiding plastic pot waste from purchased plants. There are other spring bloom plants that will be part of this plan. Wild Geranium and Solomon’s Seal will be divided and transplanted this spring. Jack-in-the Pulpit is better propagated from ripe seed gathered in early September. While Wild Columbine often produces seedlings, they don’t often transplant successfully, so will wait to collect seeds and winter sow for next year.

There is more on the Soft Landings plant wish list that will be either ordered bare root or purchased at a native plant nursery** or at one of the plant sales offered in the Twin Cities metro area this spring.*** I decided to see if a bare root, spring bloomer would be available now from Prairie Moon. Perusing their online catalog, I narrowed down to the best options that fit our site specifics, making good use of their filtering system (as Susan suggests, in her companion blog article). Plants were selected for our specifics: part-shade and shade, medium and medium-dry soil moisture, Minnesota native range, bloom time April - June, a range of heights, attractive to pollinators and birds, and finally, growing zone 4. Thirty-six plants presented themselves, but the choice narrowed to one - Bellwort (Uvularia grandiflora), an early spring bloomer, is shipped as a barre root plant, i.e. a dormant live root, packed in peat moss. This is what Prairie Moon had to say “Bellwort is an excellent early-blooming native shade plant for the woodland garden, shaded border front, wildflower garden or naturalized area. It spreads slowly by rhizomes so you can achieve a mass planting look under shade trees or along wood margins in a relatively short amount of time. The Bellwort flowers and leaves have an overall droopy appearance when in bloom. However, after seeds are set, the leaves of Uvularia take on a different look, somewhat like a needle threading the stem through the leaves…..Bumblebees, Mason bees, Halictid bees, and Andrenid bees feed from the nectar and collect pollen from the flowers which bloom April to May. Uvularia grandiflora is easily grown in average, well-drained soil in partial to full shade.” Our yard is home to several Bellworts on the northside Soft Landings. Now to introduce to the southside.

Several low-growing ground covers make their way around our yard, and I am grateful for their multiple ecological services. Common Blue Violet, Canada Violet, Pennsylvania Sedge, Ivory Sedge and Wild Strawberry stand out. These plants are valuable as insect host plants, wildlife food resources, green mulch, garden edging and more. This spring, I’ll be helping them meander to select spots, including to the Sugar Maple Soft Landings.

These are the current Soft Landings planting plans, top-to-bottom. More to grow on next month!

* The University of Wisconsin Extension has a pdf that offers several ways of managing creeping bellflower including the non-chemical method by thorough removal of all rhizomes and perennial roots.

** Most native plant nurseries are located outside of the city. I suggest taking this opportunity to visit natural areas near them, and to experience evolved native plant communities. Inspirational and educational! A visit to Outback Nursery then entails a trip to Grey Cloud Dunes, Landscape Alternatives then visit Interstate Park, Prairie Restorations on to Sherburne National Wildlife Refuge - you get the idea!

*** At the Landscape Revival on June 10th, you can meet a number of growers, native plant experts and purchase plants in one place.